GMAT Question of the Day: Daily via email | Daily via Instagram New to GMAT Club? Watch this Video

 It is currently 03 Aug 2020, 22:08

### GMAT Club Daily Prep

#### Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

# m is an even integer, and n is an odd integer. What is (-1)mn (-1)m-n

Author Message
TAGS:

### Hide Tags

Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 9254
GMAT 1: 760 Q51 V42
GPA: 3.82
m is an even integer, and n is an odd integer. What is (-1)mn (-1)m-n  [#permalink]

### Show Tags

03 Jul 2020, 01:52
00:00

Difficulty:

15% (low)

Question Stats:

82% (01:33) correct 18% (01:24) wrong based on 28 sessions

### HideShow timer Statistics

[GMAT math practice question]

$$m$$ is an even integer, and $$n$$ is an odd integer. What is $$(-1)^{mn} (-1)^{m-n} {(-1)^{2m-1}(3 + 2) - (-1)^{2n}(3 - 2)}$$?

A. $$2$$

B. $$4$$

C. $$6$$

D. $$8$$

E. $$10$$

_________________
MathRevolution: Finish GMAT Quant Section with 10 minutes to spare
The one-and-only World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy.
"Only $79 for 1 month Online Course" "Free Resources-30 day online access & Diagnostic Test" "Unlimited Access to over 120 free video lessons - try it yourself" PS Forum Moderator Joined: 18 Jan 2020 Posts: 1502 Location: India GPA: 4 Re: m is an even integer, and n is an odd integer. What is (-1)mn (-1)m-n [#permalink] ### Show Tags 03 Jul 2020, 02:01 1 Odd*even = even Even - odd = odd 2(even)-1 = odd 2(odd) = even -1^even = 1 -1^odd = -1 1*(-1)*(-1)*(3+2)-(1)(3-2) 5-1 => 4 MathRevolution I think answer should be four. Because (-1)^odd in order for the answer to be six. Kindly check. Posted from my mobile device Math Expert Joined: 02 Sep 2009 Posts: 65767 Re: m is an even integer, and n is an odd integer. What is (-1)mn (-1)m-n [#permalink] ### Show Tags 03 Jul 2020, 02:08 yashikaaggarwal wrote: Odd*even = even Even - odd = odd 2(even)-1 = odd 2(odd) = even -1^even = 1 -1^odd = -1 1*(-1)*(-1)*(3+2)-(1)(3-2) 5-1 => 4 MathRevolution I think answer should be four. Because (-1)^odd in order for the answer to be six. Kindly check. Posted from my mobile device _____________________ Edited the OA. Thank you. _________________ Director Joined: 24 Oct 2015 Posts: 530 Location: India Schools: Sloan '22, ISB'21, IIM GMAT 1: 650 Q48 V31 GPA: 4 Re: m is an even integer, and n is an odd integer. What is (-1)mn (-1)m-n [#permalink] ### Show Tags 03 Jul 2020, 02:12 MathRevolution wrote: [GMAT math practice question] $$m$$ is an even integer, and $$n$$ is an odd integer. What is $$(-1)^{mn} (-1)^{m-n} {(-1)^{2m-1}(3 + 2) - (-1)^{2n}(3 - 2)}$$? A. $$2$$ B. $$4$$ C. $$6$$ D. $$8$$ E. $$10$$ $$(-1)^{mn} (-1)^{m-n} {(-1)^{2m-1}(3 + 2) - (-1)^{2n}(3 - 2)} = (-1)^{even} (-1)^{odd} {(-1)^{odd}(3 + 2) - (-1)^{even}(3 - 2)} = (1)(-1)(-1)(5) - (1)(1) = 5 -1 = 4$$ Manager Joined: 05 Oct 2014 Posts: 54 Concentration: Technology, Entrepreneurship Re: m is an even integer, and n is an odd integer. What is (-1)mn (-1)m-n [#permalink] ### Show Tags 03 Jul 2020, 02:23 the correct answer is Option B. MathRevolution : please check once. Math Expert Joined: 02 Sep 2009 Posts: 65767 Re: m is an even integer, and n is an odd integer. What is (-1)mn (-1)m-n [#permalink] ### Show Tags 03 Jul 2020, 02:25 chipsy wrote: the correct answer is Option B. MathRevolution : please check once. _________________________________________ The OA is already edited. _________________ Director Joined: 16 Feb 2015 Posts: 657 Location: United States Re: m is an even integer, and n is an odd integer. What is (-1)mn (-1)m-n [#permalink] ### Show Tags 03 Jul 2020, 03:01 Eplanation: (-1)^even * (-1)^odd * (-1)^odd * (3+2) - (-1^even)*(3-2) = 5-1 =4 IMO-B Math Revolution GMAT Instructor Joined: 16 Aug 2015 Posts: 9254 GMAT 1: 760 Q51 V42 GPA: 3.82 m is an even integer, and n is an odd integer. What is (-1)mn (-1)m-n [#permalink] ### Show Tags 05 Jul 2020, 18:20 => $$(-1)^{mn} (-1)^{m-n}(-1)^{2m-1}(3+2) - (-1)^{2n}(3-2)$$ $$= (-1)^{even·odd} (-1)^{even-odd}(-1)^{2·even-1}(5) - (-1)^{2·odd}(1)$$ $$= (-1)^{even} (-1)^{odd} (-1)^{odd}(5) - (-1)^{even}(1)$$ $$= 1·(-1)·(-1)·5 - 1·1$$ $$= 5 - 1$$ $$= 4.$$ Therefore, B is the correct answer. Answer: B _________________ MathRevolution: Finish GMAT Quant Section with 10 minutes to spare The one-and-only World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy. "Only$79 for 1 month Online Course"
"Free Resources-30 day online access & Diagnostic Test"
"Unlimited Access to over 120 free video lessons - try it yourself"
m is an even integer, and n is an odd integer. What is (-1)mn (-1)m-n   [#permalink] 05 Jul 2020, 18:20